package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.List;

@Service
public class ShoppingCartServiceImpl implements ShoppingCartService {

    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetmealMapper setmealMapper;

    /**
     * 添加购物车
     *
     * @param shoppingCartDTO
     */
    public void add(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        Long userId = BaseContext.getCurrentId();
        shoppingCart.setUserId(userId);

        //判断当前加入到购物车中的商品是否存在
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        if (list != null && list.size() > 0) {
            //如果存在，只需要在数量上进行加一
            ShoppingCart cart = list.get(0);
            cart.setNumber(cart.getNumber() + 1);
            shoppingCartMapper.updateNumberById(cart);
        } else {
            //如果不存在，需要插入一条菜品或套餐
            Long dishId = shoppingCart.getDishId();
            if (dishId != null) {
                //本次添加到购物车的是菜品
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setAmount(dish.getPrice());
                shoppingCart.setImage(dish.getImage());
            }else {
                //本次添加到购物车的是套餐
                Long setmealId = shoppingCart.getSetmealId();
                Setmeal setmeal = setmealMapper.getById(setmealId);

                shoppingCart.setName(setmeal.getName());
                shoppingCart.setAmount(setmeal.getPrice());
                shoppingCart.setImage(setmeal.getImage());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.insert(shoppingCart);
        }
    }

    /**
     * 查看购物车
     * @return
     */
    public List<ShoppingCart> list() {

        List<ShoppingCart> list = shoppingCartMapper.listAll();

        return list;
    }

    /**
     * 删除购物车中的一个商品
     * @param shoppingCartDTO
     */
    public void deleteOne(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        Long userId = BaseContext.getCurrentId();
        shoppingCart.setUserId(userId);
        //查询购物车中的商品
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        ShoppingCart cart = list.get(0);
        if(cart.getNumber() == 1) {
            //如果商品数量只剩一个，则删除购物车中的商品
            shoppingCartMapper.deleteById(cart.getId());
        }else {
            //如果商品数量不只一个，则数量减一
            cart.setNumber(cart.getNumber() - 1);
            shoppingCartMapper.updateNumberById(cart);
        }


    }

    /**
     * 清空购物车
     */
    public void deleteAll() {
        Long userId = BaseContext.getCurrentId();
        shoppingCartMapper.deleteAll(userId);
    }
}
